1. Field of Invention
This invention relates to apparatus for staining specimens carried on microscope slides such as used in the pathological inspection of human tissues.
2. Description of the Prior Art
My prior invention disclosed in U.S. Pat. No. 3,507,292, issued on Apr. 21, 1970, has acquired world wide usage in the staining of thin histology sections cut from paraffin blocks. It is, however, not very well suited for procedures where time is of essence as, for example, when frozen sections are stained in less than one minute while a patient is under anesthesia. In addition it has found limited usage for thick specimens such as thick PAP-smears often encountered in cytology laboratories. My present invention is well suited for frozen section diagnosis and for the staining of thick specimens.
3. Disclosure Statement
Pedersen, U.S. Pat. No. 3,507,292, issued on Apr. 21, 1970, discloses an apparatus for staining specimens carried on microscope slides. Slide engaging bail 52 is pivotally secured to the body of carrier 34 so that a slide S which is supported on the bail can be lifted above the jar walls of jars 26, 28, 30 and 32 in passing from one jar to a succeeding jar. Bail 52 is pivoted about axis of central bight 54 in response to forward movement of the slides by provision of an oblique cam surface 74 positioned adjacent to the top of each jar at the downstream end of the jar and in the path of travel of depending portion 60 of bail 52 to lift the slide to a level sufficient to clear the upper edge of the jar wall. When the slide clears the front end of the succeeding jar it drops into the liquid medium contained in such jar and the staining process continues. Such drop is not abrupt because of the effect of counterweight 66. In order to avoid harmful drying of specimens in transit from one jar to the next, some procedures require machines that are so long that it often is a problem to fit them into existing laboratories. It does not provide uniform infiltration of specimens or the quick staining of frozen sections because of the slow horizontal movement of slides and the rather slow, friction dependent translation of a horizontal force to the vertical one, that is involved in slide lift.
My present invention utilizes a rotating rod to provide both agitation of specimen and the force necessary to raise it above any obstructing jar wall. It agitates slides for faster and more uniform infiltration of specimens. It can go deeper into a jar so that the upper part of a slide is stained and it can go faster than my prior invention. It can be used for the quick staining of frozen sections when time is of essence, for example, when a patient is under general anesthesia. The shorter time a patient is under general anesthesia the less risk for patient and, furthermore, it is expensive to keep a fully staffed operating room waiting undue long time for a frozen section diagnosis. It can be used for thick specimens such as thick PAP-smears.